Transdermal therapeutic systems having chambers filled with active substances have been known for some time. In particular the transdermal systems initially placed on the market comprise chambers all filled with active substances. However, production of these systems is very expensive. In particular, the "membrane bags" which are filled with active substance must be produced individually in complicated process steps, and then be applied on suitable supporting sheets as a whole.
DE-OS 37 22 775 discloses a transdermal therapeutic system for the administration of active substances to the skin. It comprises a backing layer averted from the skin, an active substance depot, a control unit controlling the release of active substance by the system, and a pressure-sensitive adhesive device fixing the therapeutic system on the skin, the active substance depot being a multichamber system wherein discrete chambers comprise one or several active substances.
Special shaping of these systems, as is described in the above document, has not been possible as yet in an economically efficient manner. Another disadvantage lies in the fact that insufficiently subdivided chamber systems, when applied to vertical surfaces, tend to have an active substance mass accumulated at the lower edge resulting in a particularly intense supply into the skin at this point, whereas delivery in the upper part takes place to a considerably lesser extent. This can only be avoided--although imperfectly--by extremely thickening the active substance mass; however, this involves difficulties in the production of transdermal systems and limits the possibilities of design.